Each of the questions given below consists of a question and two statements numbered I and II given below it. You have to decide whether the data provident in the statements is sufficient to answer the question. Read both statements and-
What is the speed of a running train ?
I The train crosses a signal post in 6 seconds
II. The train crosses another train running in the opposite direction in 15 seconds.

Options

A. If the data in statement I along is sufficient to answer the question, while the data in statement II alone is not sufficient to answer the question.
B. If the data in statement II alone is sufficient to answer the question, while the data in statement I alone is not sufficient to answer the question
C. If the data in statement I alone or statement II alone is sufficient to answer the question.
D. If the data in both the statements I and II is not sufficient to answer the question.

Answer

To determine the speed of a running train based on the provided statements, we need to analyze each statement carefully.

### Step-by-Step Solution:

1. **Understanding the Question**:
We need to find out the speed of a running train. Speed is calculated using the formula:
\[ \text{Speed} = \frac{\text{Distance}}{\text{Time}} \]

2. **Analyzing Statement I**:
- Statement I states that "The train crosses a signal post in 6 seconds."
- When a train crosses a signal post, it travels a distance equal to its own length in that time.
- However, we do not have the length of the train provided in the statement. Without knowing the length, we cannot calculate the speed.
- Therefore, Statement I alone is **not sufficient** to determine the speed of the train.

3. **Analyzing Statement II**:
- Statement II states that "The train crosses another train running in the opposite direction in 15 seconds."
- In this case, the time taken to cross another train does not provide information about the speed of the train unless we know the length of both trains or at least one of them.
- Since we do not have the lengths of either train or their speeds, Statement II alone is also **not sufficient** to determine the speed of the train.

4. **Combining Both Statements**:
- When we combine both statements, we still do not have any information about the lengths of the trains.
- Without knowing the lengths, we cannot calculate the speed using either statement alone or together.
- Therefore, even when combined, the statements are **not sufficient** to answer the question.

### Conclusion:
The answer is that the data in both Statement I and Statement II are not sufficient to answer the question about the speed of the running train.

### Final Answer:
**Option D**: The data in both statements are not sufficient to answer the question.

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